348 Hare on some Improved Forms 



again. The Galvanic Series being placed in one of the 

 troughs, the acid in the other, by a movement such as 

 above described, the plates may all be instantaneously sub- 

 jected to the acid or relieved from it. The pivots are 

 made of iron, coated with brass or copper, as less liable to 

 oxidizement. A metallic communication is made betvi^een 

 the coating of the pivots, and the galvanic series within. In 

 order to produce a connexion between one recipient of this 

 description, and another, it is only necessary to allow a pi- 

 vot of each trough to revolve on pieces of sheet copper, se- 

 verally soldered to the different ends of a rod' of metal. To 

 connect, with the termination of the series, the leaden rods, 

 (to which are soldered the vices, or spring forceps, for hold- 

 ing the substances to be exposed to the deflagrating power,) 

 one end, of each of the lead rods, is soldered to a piece of 

 sheet copper. The pieces of copper, thus soldered to the 

 lead rods, are then to be duly placed under the pivots, 

 which are of course to be connected with the terminations 

 of the series. The last mentioned connexion is conven- 

 iently made by means of straps of copper, severally solder- 

 ed to the pivots, and the poles of the series, and screwed 

 together by a hand vice. 



Fig. 1 pi. 5, represents an apparatus, consisting of two 

 troughs, each ten feet long, constructed in the manner 

 which I have described. Each trough is designed to con- 

 tain 150 galvanic pairs. The galvanic series in the upper 

 trough is situated as when not subjected to the acid. In the 

 representation of the lower trough, the galvanic series is 

 omitted, in order that the interior may be better understood. 

 The series belonging to this trough, may be observed be- 

 low it, in three boxes, each containing 50 pairs, fig. 2. In 

 placing these boxes in the trougli, some space is left, be- 

 tween them and that side of the trough on which the acid 

 enters, so that instead of flowing over them, it may run 

 down outside, and rise up within them. 



The pairs of the series consist of copper cases, about 7 

 inches long, by 3 inches wide, and half an inch thick ; each 

 containing a plate of zinc, equidistant from its sides, and 

 prevented from touching it by grooved strips of wood.— r 



